Radiator Fans and Air Con Problem

[sponger]

I have a problem!

Well 2 problems but they are no doubt related somehow!

I have an LC 180 (AUQ), turns out the air con doesn't work, I originally thought it just needed re-gassing as when you turned it on, the revs would drop with the load, however, it turned out the compressor wasn't running and the system was full of gas?

It also turned out my radiator fans aren't working?! Both low and high speed

I can put power to the fans directly, both high and low speed work.

I can put power directly to the air con compressor, that works too.

I bought a new fan control unit, changed it, made no difference

Tried bypassing the fan thermoswitch, wouldn't run the fans unless I connected it straight to the battery...
The plug pins look like this:

| <------ this one to positive terminal will run both fans?
| | <------ no matter what I do with these, nothing will run.

I don't have a wiring diagram, I have elsawin but the pictures wont come up, just get a script error

Some help/advice would be greatly appreciated

p.s. I have checked the fuses, they are fine.

 

[sponger]

I have also checked my temp sensor by plugging in to VCDS and monitoring the temp on there, matches the gauge.

 

[tombo]

Did you fix this? My fans don't come on unless the aircon is switched on, at which point the slow fan comes on. I tested both fans and they do both work.
Even in hot temperatures, sitting in traffic, the fans stay off, but the temperature gauge has not gone above 90. (I had to change the green temp sensor previously).

Interested to hear what you've found!

 

[davidcaffery]

I too would like to know if you have found what your problem is/was. I have the same situation as you tombo, my fans don't seem to come on at all unless I switch the air con on but not sure if it is slow or fast speed but also temp doesn't rise above 90 (checked through climate control ecu reading)

 

[Mark One]

Fuse for stage 1 and stage 2 fans both on top of the battery. Stage 2 is a 40A strip fuse.

The stage 1 is likely to be completely broken due to the resistor packs burning out within the motors. Apparently this is extremely common across the whole MK4 platform.

Does your aircon work while moving?

 

[tombo]

Strange! I'm thinking it's the fan control module and might try changing it. There's lots of info about the slow fan failure and reading that I found out how to test the fan at both speeds by bypassing the fan switch.
The slow fan is pretty quiet, the fast fan is like an aeroplane taking off.

I think only one fan comes on at slow speed with air con on, I read somewhere that both fans should come in at slow speed with A/C on. Does anyone know what is the correct operation?

Thanks

 

[tombo]

Thanks for your reply mark! My fuses are intact though. My Airton does work when moving as well.
Tom

 

[Mark One]

Both fans should do the same thing, regardless of mode. So you've definitely lost one of your resistor packs if only one spins on the slower mode. Not sure how long the second will take to blow

 

[Mark One]

If you are confident that your thermoswitch is working OK and bridging the wires as mentioned gives you both fan modes, then apart from wires and fuses, the only real component remaining is the fan controller/relay module.

 

[tombo]

So if one resistor pack is gone that means new fan or resistor mod?

 

[davidcaffery]

As for my situation, the air con works while on the move and both fans come on when it is switched on

 

[Mark One]

As for my situation, the air con works while on the move and both fans come on when it is switched on

But no low speed fan? Engine gets too warm unless air con switched on to kick in the high speed mode?

Resistor packs in the fan motors failed. It must be so common. I wouldn't bother with used parts, they're likely to be gone too

 

[davidcaffery]

Yeaa they seem to both be on slow speed while the aircon is on, the engine temperature seems to just sit at 90 and go no higher, that's through checking from the climate control